Aging While Posting EditionPrevious lost to fading: >>2842087Eternal thread theme: https://www.youtube.com/watch?v=7gd43b_ZcuU>New to /ham/? Read this shit!http://www.arrl.org/what-is-ham-radiohttps://www.fcc.gov/wireless/bureau-divisions/mobility-division/amateur-radio-service>Your search engine of choice works well too!>The FAQ is now back:>https://wiki.cybsec.io/index.php/HamFAQ>OP, the cybsec domain is gone.>NEW FAQ is updated to preview 15https://files.catbox.moe/aftx43.htm>The wiki is down but is archived: https://archive.is/PjR5s>Idiot's Guide to Coax Cablehttps://www.pcs-electronics.com/guide_coax.php>Looking for frequencies to monitor near you?http://www.radioreference.com>Basic Rx loop fundamentalshttps://www.w8ji.com/magnetic_receiving_loops.htm>DIY SWL Mag. Loophttp://www.kr1st.com/swlloop.htm>Small Tx Loophttp://webclass.org/k5ijb/antennas/Small-magnetic-loops.htm>In Depth Loop articleshttp://www.kk5jy.net/magloop/>Homebrew RF Circuitshttps://www.qsl.net/va3iul/Homebrew_RF_Circuit_Design_Ideas/Homebrew_RF_Circuit_Design_Ideas.htm>NEW Libraryhttps://mega.nz/file/UCgEGAjb#rwNcnMAQCUUbSp8supsFvn9QEHCWUW86eLcZa16ZG4Y>Online Practice Tests:http://aa9pw.com/https://hamstudy.org/https://hamexam.org/> Real-Time Propagation Datahttp://prop.kc2g.com/>Space Weatherhttps://www.swpc.noaa.gov/communities/radio-communications>WSJT-X 2.1 User Guidehttps://physics.princeton.edu/pulsar/k1jt/wsjtx-doc/wsjtx-main-2.1.2.html>Homosexual (ft8) guidehttps://www.g4ifb.com/FT8_Hinson_tips_for_HF_DXers.pdf>APRShttp://www.aprs.org/>Weather Fax resourceshttps://www.weather.gov/media/marine/rfax.pdfhttps://weatherfax.com/stations/>point to point predictions, its free and will give you an idea of how much power/ what frequencies to use to reliably talk to your friendhttps://www.voacap.com/hf/>how do I into Morse code in a good way?https://pastebin.com/HByjfN4F
Decided I want a citizen band radio so I can talk shit on truck drivers. What’s a good entry unit? Do I need a license for that?
>the Chad repeaters
Thoughts on the kv4p HT? Gimmick or handy?
>>2864474
>>2864474Didn't see much of it. Basically from what I read, it just connects the radio to the phone's USB via a USB bridge which allows you to control the radio through the phone vua an app. It's output is supposedly very low. This isn't new and a few chink radios have been doing this through BT. If what I read is the truth, this isn't innovative or groundbreaking. The only thing going for it is for kit builders. Other companies like gotenna and beartooth, meshtastixlc, along with many other types of LoRa devices have been doing this for awhile but with text.So gimmick.
wassup radio guyswhat's the weirdest thing you have heard on the waves
>>2864491Half the fun is sourcing your own components and soldering it all together I guess.
>>2864495I heard this guy reading a bunch of numbers, and then it repeated the next day at the same time.No, it wasn’t the time, or anything I could determine.The voice was like a 1950’s announcer.Weird.
>they keep wasting their money to DX
>>2864503If a person likes kit building, then it isn't a gimmick. That's the thing with this hobby: there's so much to it.
>>2864495Few years ago an FM station in my state occasionally accidentally played music whaile playing sports; one night this mix played for several hours and when the game ended it was basically elevator music for another few hours.So anyway somebody must've got yelled at or fired because that never happened again.
>>2864357I was listening to random websdrs for a bit over a month and it's pretty fuckin boring. Literal nontent maybe in the 50s it was cool but it's not
Hurry up and place your bid! This is a special brick!
>>2864599
>>2864505
albrecht ae 2990 afs my beloved24.890 to 29.690mhz and ssb
>>2864682Nope. Either way still nothing going on you know it too. Get on an sdr and record something cool and post it here
>>2864897Did you reached someone with that ?
You all should be like that one ham who saved lives during Helene and not like those larpers in ARES that starts fires.
>>2864925>Yes, anon do the needful; curate, edit, and post so I'm not bored.
>>2864357tap tap SCREEEECH is this thing on?
>>2865035
>>2865035 >>2865040You know he died years ago, right? And he was never a ham either.
>>2864357alr which one of you is blasting Joe Biden AI dance music on 7.2 east coast
>>2865070and...
>>2864491Late one night I came across an intermittent raspy sounding noise I initially thought may have been some form of digital encryption. Quickly ruled that out. Mystified, 3 of us monitored it for hours until we realized it was someone snoring. :-/
>>2864897What the...? That looks like a Cherokee a buddy had back in the 90's.
>>2865179its been sold with like 10 different names since the 90s
>>2865184So it has. I didn't realize it was still around in some form or another. I'm curious how well it works now. Back then I had an older Realistic TRC-211 and it worked better than his Cherokee with the stock antenna. He ended up selling it after a few months.
>>2865119You know you can use the KiwiSDR net to locate the emitter, right?
>>2865003Yeah don't just put the file in vocaroo and post it. Your whole hobby is sitting at a desk doing nothing i know you have time. Anyways there isn't anything to to record so whatever I know
>someone actually paid $180 for a brick
>another meshtastic video
>>2864599no you are correct, though peak shortwave was the 80's. nothing worth listening to anymore especially in the US.
>contesters literally broke into our netFuck contesters. I hope they die an agonizing death.
>>2865617My father bought me a brick from Indianapolis Motor Speedway for Christmas last year, I thought it was neat. I'm sure some ham probably thinks this is equally neat, though I wouldn't care about ARRL bricks.
My callsign is F4GG0T, FOXTROT FOUR GOLF GOLF ZERO TANGO. >be me>talking about the weather to my friend>hear a disturbance >Man with a Chinese radio starts talking>ask him for his callsign>he’s fucking unlicensed>tell him I’m going to Foxhunt his ass>get up out of bed>walk to the door>nursing home door is locked>nigger nurse drags me back to bedF4GG0T SIGNING OUT, CATCH Y’ALL NEXT TIME
Hi /ham/! Got a question for you. Some background, I got limited space to hide coax. SMA coax would fit, whereas the beefier kinds like SO239 wouldn't. My rig can go up to 100 watts (no amplifiers). My question is how high of power can SMA cables handle (I'll need about 80ft)? I plan on putting up an OCFD that can go up to 80m. I have plenty of room for that long of a dipole while staying out-of-sight.
>>2866667SMA is just a connectorYou can put sma connectors on big coax and you can put PL-259 on thin coaxpower rating is best obtained from the manufacturer of the cable.But good coax isn't cheap and good thin coax certainly isn't cheap.
>>2866667the problem is the voltage that can go very high with some antennas, so insulation is important. SMA will have a maximum tenson lower than BNC and that will be lower than N or UHF. If there's arcing it's a short and the final amplifier of your rig can be killed. Problem is voltage will be difficult to calculate.Amphenol, a reputable brand, gives 75W for 10 GHz max :https://www.amphenolrf.com/rf-connectors/sma-connectors.html316W for 1 GHz for BNC :https://www.amphenolrf.com/rf-connectors/bnc-connectors.html500W for 300 MHz for UHF :https://www.amphenolrf.com/rf-connectors/uhf-connectors.html
>>2866688I do have a jumper I use to go from inside to outside. To the outside is sma while inside is pl259. The sma is used so I didn't have to drill a bigger hole. I just really want to know if it'll still be good to use the thinner coax, which>>2866793 answers.>>2866793If it's 75 watts for really good sma coax, then it's a bust. I'll just have to find a way to conceal the lmr so239. Thank you for answering me. I think I can find a way. I may just have to bury it like I had to do with the long wire antenna's coax.
>>2866808if you read his links HF is well above that since the power handling reduces the higher the frequency.
>>2866793>voltage that can go very high with some antennasTrue. Isn't the J-antenna used to avoid just that?
>>2866818Exact. The best is to try with a swr meter behind the TX, increase the power gradually, if there's a problem the swr meter will show high swr
>>2864357Started using FT8 now I've finally got it working, great to make so many connections around the world but is it normal that only around 1/10 reply to my calls or is that a sign I'm too weak in my transmissions?Was looking into remote control for the radio but it seems all of the software is quite expensive, i'll probably buy deluxe or w/e it's called though as would be good to do ft8 in the living room rather than going into the shack.
>>2868139What signal report did you get from the ones that replied? You can look at pskreporter to see how far you are getting out without the replies to your call. It should give you an idea where you getting out and who is getting your signal.
>>2868152The signal report I get is not great usually in the negative, but I often call people that are close enough that they should easily be able to hear and respond and they don't, the only thing I can think is that they are waiting for specific countries and not mine.
>>2869330>call people that are closehow close? HF tends to skip
>not making the 135.7kHz dipoleYou are not a true ham radio operator until you have this antenna resonate and 1:1 swr.
>>2869425I wish I had the real estate to do something like that.I once saw a Lowfer set up for around 170 kHz. A base loaded ~40 ft guyed vertical with a 6ft tophat. The primary coil was 14g copper house wire wrapped around a Rubbermaid garbage can. The matching coil inside it was copper wire wrapped around a paint can. I don't recall the ground system he had. 1 watt slow CW.
>>2869425Last time this came up, we found that the Golden Gate Bridge would be a good armature for such an antenna. At such a low frequency I guess the antenna will have to be made of a silver tube.A resonant loop antenna, though...
Hey, /ham/, I have seen a lot of interesting antenna arrays in Tokyo. (pic related)Does anyone know what these arrays are used for / at which frequencies they operate? I have only ever seen them in Tokyo (or atleast nowhere in Europe or the USA)Reverse image search doesn't come up with any meaningful results.Here are a few things to note:- they share their position with cellular equipment.- they are connected to what looks like standard cellular RRHs (remote radio heads)- each antenna has two cables connectedNormal cellular sector antennas also have two coaxes each. (for each channel)However they are fed +45° and -45° signals matching the 90° phase difference of the radiating elements that are also placed 90° to each other.But how would you have two 90° elements inside a stick antenna like this?- they seem to always have an antenna in the middle of the array- to me it looks like a directon finding array with a reference antenna in the middleAny information and feedback is very welcome. (Use, system, antenna type / manufacturer, etc.)
>>2870205Here is another shot of a different array.
>>2870206>>2870205I have no idea what it is but it looks like that :https://ja.m.wikipedia.org/wiki/W-OAM#W-OAM_typeG
>>2870208Thanks, this looks like a good start.I will look into that.
>>2870205>>2870206>>2870210and or thathttp://www.asahi-net.or.jp/~yj3k-ssk/PHS.st/CS8EL.htmlit seems to be linked to W-OAM, Willcom OAM, japanese specific cellular network in the 2000s
>>2870210https://ja.wikipedia.org/wiki/%E3%82%A6%E3%82%A3%E3%83%AB%E3%82%B3%E3%83%A0Willcom company wikipedia page in japan. Myabe it's a 80mhz cellular network, but I am not sure, google translation isn't good
>>2870210Finally in englishhttps://en.wikipedia.org/wiki/Personal_Handy-phone_Systemfrequency around 1900 MHz so these are colinear antennas, it provides a huge gain and they are omnidirectional in azimut but with a horizontal beam on elevation, no need to talk to the sky
Which one of you started this just so you can pretend to be important by providing emergency communications?https://nypost.com/2024/11/10/us-news/deadly-nj-wildfires-continue-to-rage-leaving-region-blanketed-in-smoke/
Sounds like >>2870441is the answer
>>2870205Strangely, it seems that there are two, in one cae three, cables entering each antenna. Why would that be is these are colinear antennas?
>>2870616maybe one band is Tx and one is Rx and there's a splitter / combiner at the bottom of the antenna
>>2870616This is what I am wondering as well. Each antenna also seems to have a small enclosure, similar to some older LNBs.Maybe they have some kind of active filtering / low noise and or variable gain amps or something. The second cable might just be power and some kind of control bus. It does look similar to the small motor box that is used to set the phasing on the sector panels but this wouldn't make a lot of sense on these.>>2870626Also an interesting idea but for once a colinear antenna is propably to narrow band for both bands and putting the duplexer on the antenna would only double the amount of coax needed. Still something to keep in mind I guess. I was hoping to come across one of these antennas in some electronics store in Akihabara but no luck there.
>power up frequency counter>display background glows but LCD is blankArgh!Matrix style LCD with fluorescent blue background (no backlight). Open up unit. Reseated ribbon cable to display numerous times, voltage regulator output is perfect. What causes this? :-(
is the quansheng that youtube is shilling actually good? usb-c is nice
>>2871001they are easily firmware modifiable so that's the primary reason for their popularity not sure if the RF section is really any better
>>2871001modulation is good, far nicer than baofeng, from stock, with the firmware I got, it's even a bit better.they are cheap as fuck, can do a lot of things as >>2871025 said, the firmwares give a lot of possibilities. Funny that a good antenna will cost as much as the radio kek
>>2866334kino
>>2871027any rec for a good antenna? sorry if noob question
>>2871153no reason not to ask, anon, the diamond SRJ77 can be a nice addition, it costs as much as the quansheng kekyou can go with a real (there are more copies than original) nagoya NA-771 with female SMA too, cheaper but good quality still
>>2871105There's that kid word again.
>>2871274It's okay boomer, you'll understand the lingo one day.
I got a CB radio for free. What's a good budget antenna setup for an apartment? Couldn't I grab a 50 dollar magnetic antenna and slap it on a cookie sheet instead of paying 150 for an A99?
>>2871437Get a used one for dirt cheap, get a nanovna to test your setup. 5/8 doesn't need radials, 1/4 needs them
>>2871437dipole taped to a window
Plz forgive, I am new>>2871447Used magnetic/mobile, you mean?>nanovnaI assume that fulfills the role of SWR meter?What's a radial?>>2871480I assume picrel with the middle part taped to a window and the ends taped up/down against a wall?
>>2871607>>2871437I did get a successful (but noisy) receive on the antenna that came with my SDR.
when I was a kid, about 10yo, I had a small radio that I used to listen to cassettes on, I once attached a length of copper wire to the the antenna, wrapped the wire around a piece of quartz after about 20cm and then hung the rest out of my bedroom window. I forced the dial on AM band to the highest it would go and heard Morse Code. I did the same on FM and heard what I thought was taxi radios, turned out they were airplane frequencies.
>>2871607>Used magnetic/mobile, you mean?yes, or maybe a base station antenna if you can find one not too cumbersome>>nanovna>I assume that fulfills the role of SWR meter?yes, you can trim your antenna to the frequency you'll use>What's a radial?like a counterpoise, in picrel the antenna on the left has radials, it is 1/4 of the wavelength (300/freq in MHz)
>>2871447>>2871652>Get a used one for dirt cheapMost of the ones I'm seeing on US eBay are unbranded and run about 30 bucks after shipping, about as much as a new one, picrel.Is there a certain type or model I should look out for? Or, am I supposed to look elsewhere? (Facebook groups, swap meets)
>>2871607You can tape it up vertically for local and horizontal for dx.
>>2871731too small, you'll be frustrated and it's a waist of your money.
>>2871772>>2871652Does the thickness of the cabling matter for the SWR meter? I was thinking about putting a cheap adapter cable between the radio -> vna and using the regular thick coax cable + an adapter for antenna -> vna
>>2871844no it's ok, it matters for power handling and loss at high frequencies (above 100 Mhz)
I'm gonna start working on/restoring an old tube ham radio. Do I really need a VTVM, or will a 1GHz scope + RF probe work fine? I'm looking at a $15 one from Ukraine on ebay
>>2871908all you really need is a meter, audio signal generator and a scopeyou've been watching too much Mr. Carlson
>>2871911and a dummy load ofcassuming it's a transmitter
>>2871911>meterWhat kind of meter? DMM, SWR, power meter, etc. Fortunately I have all three>audio signal generatorWouldn't I need more than a few kHz in order to cover the actual radio bands? Like at least 30MHz for 10m and above?>Mr. CarlsonI have no idea who that is
>>2871959I'll chime in here too. A radio buddy (now an SK since 1999) used to build tube CW transmitters and receivers. He had the following test & measurement equipment: tube tester, analog multimeter, dummy load, a 10 MHz oscilloscope, and an old Heathkit RF signal generator that covered from the AM band to 30 MHz or so. Being an old guy he was comfortable with the analog equipment. He also had a cheap digital multimeter so he could measure capacitors. I think his analog meter could measure inductance too but i'm not sure now. With that, you are set.An RF signal generator can usually modulate an audio tone within the human audio range onto an RF signal that obviously has the range to cover the HF radio bands of interest.'Mr. Carlson's Lab', a great youtube channel. He restores and repairs radios as a profession. I'm about a 45 minute drive from him.
>>2871959audio generators are good for the voice amplification section of transmitters which are one of the first parts to go. Plus it makes it easy to follow the signal path through amplification.For receivers you do need an RF generator especially if you're doing alignment.
>>2871996>>2872007I have an old Heathkit signal generator that has a switchable internal 400Hz audio tone, as well as a more modern Wavetek generator, so I think I'm set on that front. In addition, I have a dummy load, nice Fluke DMM, and 1GHz Tek scopeI'll have to check this Carlson guy out
> 20 foot coax + dipole antenna + nanoVNA is $130>for a $5 CB radio Couldn't I just slap a $40 firestik on it and call it a day?
>>2872183absolutely
It seems my base station options under $50 are:> 5/8 Firestik and have a 3 foot dong hanging off the back of my radio>TRAM 703-HC mag mount antenna with tinfoil ground plane, and maybe a shitty $25 swr meter or cough up for a VNAWhich one would you guys go with?
>>2872208shitty swr meter, look if you can't find one used for cheapfor the antennas, the longer the better, I am not sure you'll pick up anything with a 2ft high antenna
>>2872208Personally, I wouldn't chose either. I'd cut a wire dipole and throw it up into a tree. But using your restrictive parameters i'd go with the mag-mount. It looks like the quickest & cheapest way to get on the air and would give me the ability to slap it on my car and go mobile if I wanted to. Both of your listed antenna choices are compromise antennas so I don't think one will give better performance over the other. And with the Firestick it looks like you need to get a mount for it.
>>2871625When I was about 13 I was playing around with one of those Radio Shack 150 in 1 electronic kits they had back in the day. I was experimenting with the AM radio circuit and connected it up to our clothesline hoping to pull in a distant FM rock station. Dial had no frequency indicators so I tuned around and heard continuous repeating morse code. I copied the dots and dashes and showed it to my Electricity teacher who id'd it as an LF airport beacon about 6 km away.
Anyone ever build their own antenna tower? What's the highest tower one can build by themselves without the need of heavy equipment or 2nd hand help? Are there any kits that allow you to move different antennas up there without the need of climbing it?
>>2872712the better question is what you can get away with in your town/county (assuming US)but a quite tall tower can be built with nothing but a gin pole. You're gonna need a concrete truck for the base though or you're gonna be mixing a lot of concrete. For a rohn g series tower the pad is 2.4 yards of concrete, they go up substantially from there.
>>2872712>move different antennas up there without the need of climbing it?How do expect to secure the antenna or run the coax? Magic? A team of humming birds?
>>2872712to access the antennas easily the tilt over mast can be fine, assisted with a winch, there can be heavy stuff on the mast and you'll be able to get it erect by yourself
>>2872727https://www.youtube.com/watch?v=mynik3R4ySUI have a 6m long tube secured to the side of my house and I am considering doing something like that, or maybe with a vertical movement so that I can access the top of the mast on the roof (very easy to climb onto the roof)
>>2864357Question about FRS GMRS.BLUF: How do I input the privacy code portion of what is FRS channel 22 plus privacy code 6 into the UV-K5?I have a Motorolla FRS walkie talkie that is picking up conversations from WAY farther away than it should on channel 22 with "privacy code" 6. It is just barely able to pick up the transmissions. I also own a UV-K5 with a much better antenna, which could receive these guys better. I can easily input what is the FRS-GMRS channel 22 which is just 462.750 but I have been looking at the manual and I cannot figure out what a FRS privacy on a basic level actually is, or how to input it on the UV-K5. I can hear Channel 22 on it just fine but I can't figure out how to make it listen to channel 22 + whatever Motorolla says is privacy code 6.Thanks in advance.
>>2872480So basically $100 is the sweet spot? >>287218325 bucks for a crap SWR meter, say $20 for speaker wire and an so-239, $40 for a good run of coax cable (or $20 for a yellowman special), totals around 60-80 bucks for a DIY dipole and $80-$100 to get one premade.
>>2873217>>2872480Realistically speaking, how big is the difference between a dipole and a magmount in an apartment? I'm probably not going to use the radio that much.
>>2873218Mag-mounts don't work well inside. If you're using it for CB, the verticals with loading coils (the short whipped mag-mount kind) are absolute trash. If you're using it on 2m or higher, you are better off making a 1/4 wave ground plane. No, sticking a mag-mount to a sheet pan does nearly nothing for reception and less for Tx. If you're just listening, throw a piece of wire about a half wavelength out the window and stick the end in the center of the antenna connector, no coax needed. If you insist on using a vertical inside, I'd suggest a rubber duck. However, if you're transmitting, you'll be disappointed with any of this unless the antenna is outside. You still need the SWR meter for a pre-made antenna, dipole or mag-mount, as they still need to be tuned.
If you want something that will take minimum effort, pic related plus some coax cable will get you by.
Just don't expect to talk to the moon.
>>2873349Well for what it's worth, when I got my first radio (Icom W2A) I was loaned an old Radio Shack CB magmount that had been trimmed to provide a near perfect match at 146.520 MHz. Stuck it on top of my fridge. Got into our local repeater 24 km away nearly full quiet at 0.5 watts. I placed it on a cookie sheet and put it on the roof but had to bump up the power to 1.5 watts and while copyable, there was some white noise. Back on the fridge it went until I rigged up a 6 element quagi. Got me on the air.
I have a yeasu FT-2980, the power is directly connected to my truck battery. I didn't want to mount the antenna on top of the truck cab so I installed a mount behind the truck cab on the passenger side. When I'm driving I hear a fuzz sound when ever someone is broadcasting. So my question is, am I hearing this sound because I did not mount the mount to bare metal so it is not properly grounded? Or is it because I did not secure the coax cable properly under my truck?
>>2873754you're hearing your alternator
>>2872789When I was a kid everyone had a TV antenna “tower” next to their house constructed like the one that the guy in picrel is hanging on to.Like, there must have been millions of them.what ever happened to them, are they still legal (I assume they are), does anyone still have one, and can they be re-purposed for other RF functions?Even the flintstones shows houses with these big TV antennas. Why is it such a b*tch to get one of these nowadays
>>2873773How so? Sorry I'm still new to ham
Actually read why it could be the alternator, thanks for the help. Looks like I'll reroute it going on top of the cab.
>>2873777Towers weren't common, antennas on the roof or chimney were. Towers need a cement pad, which is a large investment (time and money wise) that people didn't want to undertake. Don't get me wrong, some weirdos had towers for TV reception, but it was not commonplace.
tl;dr I need a way to attenuate my neighbors wifi at my router. I'm trying to make a link from my house to shed but speed is trash. I know it's interference because when the power was out i had battery backups and the speed was blazing fast.I've tried making a shield out of aluminum flashing that surrounds the router on the sides that face the neighbors and then grounding it but it made no difference. Is there a way to do this?
>>2873933Are the antennas on your router detachable? If so, connect a coax to a long Yagi, and you get a very directive beam.
>>2873943Nope. Internal antennas. I messed with it a bit more and soldered the wire to the metal sheets. it takes down the neighbor's wifi from -68 to -70 now but there has to be a way to to take it into the 90's right? Instead of grounding it to the house's ground do i need to ground it to the router's negative? Do i need to block signals on the top and bottom too?
>>2873948You're going to burn out your finals, bro.
>>2864357US ham reporting in.Looking for a SDR upgrade which I can grow into.I have 2 ghetto, fake RDL-SDR dongles, but played with a VM OpenWebRX install which allowed me to incorporate both dongles into a locally hosted site.That may have sounded like a bunch of noise in which case I plugged in a PC on the unfinished side of the basement, ran 2 antennas to it, and now I have a website I can visit on my local internet that gives me a waterfall that blows N1MM out of the water.I see the potential of this in ham (and further) activities. It'll be a journey to upgrade the antennas and the dongles, but I thought I'd start with the dongles.Where do I go from knockoff RDL-SDRs? I was kind of eyeing the SDRplay RSPdx which has 3 antenna inputs, but it turns out they come with their own software. which I'm not interested in.
>>2874011I have the SDRplay RSP1B but I agree in that their own software package is annoying and I wish they opened up compatibility but they're Brits so what do you do. You could look at airspys or something similar
>>2874012I appreciate it. I started looking at the Airspys today, then saw the SDRPlay with 3 antenna inputs and was temporarily hooked, but became disenfranchised with their software. Apparently it can be incorporated into OpenWebR, but after comparing all the SDR products, setting up a OpenWebRX environment, playing with antennas, troubleshooting, and thinking of all of the possibilities and future possibilities today, I'm a little inundated.It's kind of a mind breaker to think you're spending a lot of money on a SDR for the HARDware when SDR is an acronym for SOFTware.
>>2873777Probably removed over the years by people who may have wanted a cleaner look to their home after switching to CATV. A lot of those antennas were looking pretty rough after decades of weather exposure. Many were removed when the roof was being re-done. Most of the ones I saw and still see to some extent, are on small rooftop tripods or the pipe mast is bolted to the side of the house or chimney. I didn't see many towers except out in the countryside.Over the years i've been offered so many antennas. Homeowners just wanted it off their roofs. I actually took one for my old apartment but left it behind when I moved. Wished I had kept it. Whenever I see them I ask the owner if they want to keep it and they all say yes as they use it for the free OTA HDTV. I think that's why finding surplus antennas is difficult.As one customer told me: as a kid in the 50's he had to go outside regardless of weather and spin the antenna by hand when changing channels (his father was too cheap to buy a rotator) to another station in another city. By late 60s he was on cable so no more of that nonsense. He ditched cable by late 2000's and has now dumped streaming because it sucks and has gone back to the old antenna on the roof but now with a rotator.He's gone full circle. :^)
>>2873948There's a bunch of wifi channels, put an app on your phone and find an unoccupied channel and set your router on it. And if you have a dual-band router and use only one band, disable the other band you're not using.
>>28740601, 6, and 11 are all swamped. 5 and 6 ghz doesn't reach.>>2874004This is a wifi router, not some multi-watt ham setup and theoretically the plates should be absorbing the signal and feeding it into ground right?
>10m dying by the time I get home from workI remember an dude telling me a vertical would be dogshit on 20m. Not even worth using. Built one using under $20 worth of EMT pipe from home depot and a roll of wire I had in the garage that I got for $7 at a garage sale. Only has 20 ~18' 14 gauge radials. Cut a hole in a bucket and mounted it to a few pieces of shit I smacked into the ground, the bucket is an insulator from the radials in case of wind or coyotes. Fired it up, 100w barefoot, <1.5 swr across the band (dip is only down to 1.3:1) and made an immediate contact to Russia on sideband. Then made contacts into Alaska, Hawaii, Mexico, Canada, Brazil, Haiti, and Columbia in about 3 hours. All sideband.Yes, that's duct tape. Held it through 40mph winds and a light drizzle last night, 0 issue. I consider this little antenna a success. Maybe I should build a second and run them in phase.
>>2874130No, you're reflecting the rf right back into your router and cooking it.
>>2874136Do you have s30 noise floor in that spot?
>>2874264Nope, I moved out here earlier in the year and compared to Vegas there's barely a noise floor. Like an s1-s2. It'd be closer to an s9 in vegas.
>>2874136I like it! It may not be elegant, but it works.>low noise>room for radialsI'm envious. My last QTH was in a remote area with low noise and the landlord was ham radio friendly. Not so much now.
>>2874136Wouldn't a dipole be better?
>>2874478a dipole can be less noisy for receiving but the low angle of attack of a vertical can help for DX
>>2874478Dipoles require height, an equivalent dipole for 20 meters would require 30 feet (half wavelength) of height. It's also directional, so you need to rotate it or have 2 set up. If he doesn't have trees or proper push up masts installed to handle the wind load of a 32ft antenna, a vertical will suffice. Also, he has low noise anyway, so the noise cancelation of a dipole might not be as beneficial as it would in a high qrm environment. Verticals are also low angle radiation (good for dx) and great as spotter antennas on bands like 20m, where you might have propagation to both Asia and Europe from the Americas.
Hey fellas, I'm a pepper guy and I went down the entire ham rabbit hole. Recently I've been looking into Gmrs, and I'm wondering why it is not promoted more for people like me.Are there any major limits compared to Ham if I have no plans of using repeaters? It seems fsr easier to get a bjg group of people into
>>2874589I too enjoy the cool refreshing taste of Dr. Pepper.
>>2874589GMRS/FRS and ham are very different and for different purposesGMRS is good for local communication with other people and families. It has effectively replaced CB in such roles.Amateur radio is fundamentally more about the tech. So by being licensed you get the permission to run different modes, more frequencies and higher power.A technician class license is a very limited intro to amateur radio and the true feel of ham radio would be general class HF operation.
>>2874656I'm aware of the difference, but I'm more asking is if someone gets ham exclusively for baofeng type set ups and doesn't plan to use repeaters, wouldn't the gmrs be better?
>>2874658yesalthough technically baofengs aren't legal for GMRS/FRS but you do you manit does make a lot more sense for prepper use
>>2874589>I went down the entire ham rabbit hole>Are there any major limits compared to Ham if I have no plans of using repeatersYou have to be fucking kidding me.
>>2874739the classic YouTube prepper to radio rabbit hole
>>2874745There's a whole thread to read and he doesn't understand propagation and worldwide comms in an emergency. Just walkie talkie gmrs. We have hams building antennas from home depot dumpster scraps here and he doesn't know if ham has a benefit to gmrs in an emergency.
>>2874589>Are there any major limits compared to Ham if I have no plans of using repeaters?Yes. Range and available (digital) modes. When you have a /ham/ license, you will also have learned how to communicate with little or no chance of being found. A stint in Signal Service also helps.
Hey all, looking for some info on SDR setups for a particular purpose.My father in law is a retired EE. He obstinately refuses to get cable and only watches broadcast TV. The reception at his place is godawful and he keeps claiming there’s an illicit broadcaster interfering with the signal. I’m pretty sure his aerial is shit, wiring to the aerial is fucked, or he’s getting interference from old appliances.Anyway I’ve been looking for an excuse to get a SDR dongle for years and this seems like one. Do they pick up NTSC digital broadcasts? Any other suggestions?
>>2874816The cheap RTL-SDR dongles are NTSC receivers. That's their primary purpose.
>>2874823Okay great so any RTL-SDR dongle will work? Imma freak him out when I come over for Christmas haha.
>>2874986The main site for those is this one:https://www.rtl-sdr.com/There are cheapo Chinese clones that overheat and stop working, so there is an element of risk. If you buy from this site you are more safehttps://www.rtl-sdr.com/buy-rtl-sdr-dvb-t-dongles/I don't have interests in that shop but I am looking to buy one myself.
>>2874589Hf band access
>>2874809I never get hiw everyone always thinks comms are nothing but hts, esp the preppers.>building antennas from home depot dumpster scrapJust trash in general. My attennas are just a bunch scrap wire from appliances spliced and soldered together until I got the lengths I get a lot over the length I need, then trim to tune as needed.
>>2875257You could just fold it back instead of trimming.
>>2874823>>2874986RTL-SDR dongles are DVB-T receivers. They can't do NTSC. Even if they could, NTSC has been obsolete for years and no one broadcasts it anymore. You would need an ATSC receiver.
>>2875287>ATSC/NTSC/DVB-TYep, my bad. Got the acronyms mixed up.
>>2875287>>2875303Okay does it cover the same frequencies? I just want to be able to see the shit happening in the spectrum where the TV channels are. I’m just looking for interference, not to actually decode the TV broadcast.
>>2875574Yeah, I think even the shitty ones can tune from 30MHz to 1.2GHz with 2MHz bandwidth. Check out the rtl_power utility if you're on Linux, it scans around and merges the samples to create a bigger waterfall, at the expense of temporal accuracy.
I just noticed that Yaesu released some new/revised mobile mobile rigsThe FTM-150RASP actually looks pretty decent, nice simple vhf/uhf without all that digital garbage. Something I would actually put in a vehicle.
any non boomer guides to QSL cards?
>>2877096I only know how to send them to regular hams "via buro", you give them to your local ham club and they send them to the national ham association and that association sends them to the other guy national association, then to the other guy's local club and he go there collect them.I suspect "direct" means via regular mail but for some stations, you need to send some money so they send you a QSL backI didn't print any yet, I use eqsl, I am a bit shameful to not send back paper QSL to the guys who sent me some
>>2877136that's where I'm atmy regions qsl bureau was just letting me know that I had some cards waiting there and I started thinking that I don't even have a QSL card design to send.I'm assuming these cards are from japan, since that's the only DX I have so far. Guess I'll see when they show up.
>>2877096Send them direct unless you are sending one via DX. I'm not paying for some one sending me cards through the bureau. I'll pay to send my QSL card if they send it to me direct and I'll also send them direct.
>>2877096>non boomer guides? ? ?
Say I wanted to operate an old hotel style analog TV network only instead QAM to NTSC it's ATSC to NTSC. What would be the most efficient way to go about it? My best thought currently is using SDRs to generate several channels per radio. Take the HackRF. 20MHz bandwidth so I should be able to do 3 channels per radio then mux the outputs.
>>2877096Don't bother. E-qsl, qrz, and lotw all replaced the need for qsl cards in every capacity. If you make contact with rare dxpedition areas or something you can always order a card, or email the email on their qrz and ask if they'll send one (usually they will for a few bucks) if it's an area you really want.
>Meshtastic!!!
>>2877270You can find brand new NTSC modulators for under $20 on ebay/ali.
>>2864357can you guys recommend me any decent inexpensive SWR meter? I am very new to the topic and I wanted to make a decent HF antenna.
>>2877826A nanovna will be good enough for hf if you calibrate it correctly. If you cn get a mfj something used for less than the nanovna, get it only if you are certain it functions correctly
Can someone recommend a good, general, diy receive only antenna? While a ham, I also setup a SDR to have a second set of ears. I ran a wire out to my gutters and the receive signals are abysmal compared to my vertical that's 50 feet further away.
>>2878477>recommend a good, general, diy receive only antenna?A plain dipole cut to the length of the signal you are expecing will be fine.>I ran a wire out to my gutters and the receive signals are abysmal compared to my vertical that's 50 feet further away.Is it in contact with the gutters? Moost likely, the gutters are grounded, effectvely shorting out your antenna.
>>2878477to receive you should prefer a symmetrical antenna, it's less noisy than a non symmetrical one like a vertical or a long wire. Something like a G5RV, a loop, folded dipoles like picrel
>>2878477or like picrel
>>2878487>A plain dipoleUntil now, I was suspecting the ground was irrelevant because I was looking for a broad receive only. I guess receive only isn't that far off from rx/tx antennas.>Is it in contact with the gutters?Bare wire wrapped around a screw into the gutters>>2878488>>2878489I've made quite a few antennas through the years. In retrospect, I was dreaming a wire screwed to the gutters would become some magical beverage antenna for all frequencies.Guess there aren't any shortcuts for receive antennas and I should think about a switch box and antenna farm.
>>2878495>Bare wire wrapped around a screw into the guttersTry putting an insulator between the two.
>>2878794I have a shed with electricity about 50' from the house. I think a better answer is to run ethernet to the shed, setup a raspberry pi out there with OpenWebRX on my network, then feed the pi with some tuned dipoles or verticals.Then from my shack in the basement I can have an additional set of ears
>>2864357yo im kinda new to this, i got into this shit with the military using radios made by Thales (picrel)I'd like to get into this but it's such a different world in civilian, ours get about from 0 to 100Mhz where do i find that kind of stuff ? all the stuff i see is like in the 400Mhzalso what band is considered FM is it just the lows of VHF ?
>>2879060Are you talking about amateur (ham) radio? Find a local club and hang out. Like it?? Then get licenced. Most hams can guide you from there. Most of our HF gear goes between 1.6 MHz and 30 MHz with some models that go as high as 50 MHz. Some will even cover parts of the VHF/UHF spectrum as well.>also what band is considered FM is it just the lows of VHF ?I'm in North America (ITU Region 2). NFM is typically used in the authorized bands from 50 MHz up to 1.2 GHz. There is the occasional FM use in the 28 MHz band but not too often. You'll find 95% of FM activity on 146 MHz and 446 MHz.
Can i get into radio without doxing myself to the federal government?
>>2864357..why isn't there an open source VARA? isn't it just COFDM with a protocol for telling the source to step up or step down modulation? https://www.sigidwiki.com/wiki/VARA_HFnothing new or special here at all
>>2879604why can't you just use your radio without a license?> inb4 "NNNNOOOOOO THE FCC!!"go back to rddit
>>2879607i don't fear the FCC, i fear old boomers driving around with vans full of network/spectrum analyzers and directional antennas.I just want to set an an aerial and play around with things without having glowies show up at my home.
>>2879604Yes: it's called CB.
>>2879613Don't transmit on the bands where the boomers will be looking for you, the ham bands obviously. There's always at least one faggot on here who will tell you you're being a bootlicker or whatever for not doing it, ignore them. If your goal is to play on the radio without being a nuisance to anyone on purpose I think you can find a way to do so. Just stay away from licensed users.
>>28796136.666 MHz (and around) and CB bands are for you then
>>2879060>yo im kinda new to this, i got into this shit with the military using radios made by Thales (picrel)If you used those radios, I guess you have been around for a while.>I'd like to get into this but it's such a different world in civilian, ours get about from 0 to 100Mhz0 MHz is impressive.>where do i find that kind of stuff ?Not sure what you mean, did you mean civilian ham rigs for those frequencies? Yaesu FT-991A might be what you are looking for.>all the stuff i see is like in the 400MhzThere are /ham/ bands in that area too.>also what band is considered FM is it just the lows of VHF ?Also around 28 MHz with CB radios.
Everyone doing these class E amps does the top.Why wouldn't you do the bottom?
>>2879060>0...MhzThat's going to be a long dipole.
>>2879987>3449 ftEasy mode.
>>2880186Hmm.. that reminds me, I need to dig out my Rigblaster Advantage.
>>2880201I use a RIGblaster plug n play with my Yaesu. Pretty happy with it. I use it without CAT, but still am able to Tx via serial.
>>2865913Is there anything wrong with meshtasic? There are a couple of nodes where i live so i thought about spending 30 bucks to join. Anything i gotta know before jumping on 868 MHz in germany? Some sources say you can use half a watt and some say only a quarter, so which is it and when?
Hey /ham/I found this tranceiver on a scrapyard. I want to restore it if possibly. It doesnt have his power source.
Anything i am doing wrong or does the RTL-SDR just not work outside of FM frequencies? I managed to get something out of 70cm with direct sampling on the q branch but for some reason i cant replicate it. All i get is extreme noise.
>>2880808>does the RTL-SDR just not work outside of FM frequencies?It should work well outside the FM band, see specs:https://www.rtl-sdr.com/about-rtl-sdr/>Depending on the particular model it could receive frequencies from 500 kHz up to 1.75 GHz. If you have extreme noise, you might end up overloading the frontend and things will go nonlinear. For a quick check, try adding an attenuator to see where the noise is, then add a filter against those noise signals.
>>2880774There isn't, but it's ridiculous how often it's spammed as some new legendary fix all solution to text messaging without major infrastructure. It's nothing new, gotenna has been at it for much longer.
>>2880778Looks like it could be a fun project. Good of you to save it from the scrap heap.
>>2880281Yeah the Rigblaster stuff seems pretty solid. I've never heard a complaint. I stumbled on mine a couple of years ago that some guy in the next town over was selling. Mint shape, has all the packaging, manual, cords, etc and even better: he used it on the same model of Yaesu I'm using so it came with preconfigured cables.I'm looking forward to getting this working. But right now i'm struggling to refurbish a used Yaesu ATAS-120 antenna that's all seized up.
What is the best chink handheled han radio? It has to have a removable battery, usbc and be unlocked.
>>2880951quanshengthey don't recommend charging the battery with the c port on the radio thoughbetter to get a different battery with the USBC charge port on it
>>2880951Tid h3
Clean up your clutter, stop buying happy meals, stop being lardasses. Why are hams so fucking fat?
>>2881060Why are you perpetuating this cliché? Meanwhile, in Japan: https://www.youtube.com/watch?v=m-B8KHqofF8
>>2881073>the exception is the ruleHow fat are you?
>>2881077Not at all, perfectly normal BMI according to European standards.
>The World Morse Code Championshiphttps://hackaday.com/2024/12/17/the-world-morse-code-championship/>If you were in Tunisia in October, you might have caught some of the Morse Code championships this year. If you didn’t make it, you could catch the BBC’s documentary about the event, and you might be surprised at some of the details. For example, you probably think sending and receiving Morse code is only for the elderly. Yet the defending champion is 13 years old.>Teams from around the world participated. There was stiff competition from Russia, Japan, Kuwait, and Romania. However, for some reason, Belarus wins “almost every time.” Many Eastern European countries have children’s clubs that teach code. Russia and Belarus have government-sponsored teams.
>>2881073>Icom saleslady is the perfect embodiment of the jap ham community and totally not a saleslady
>>2881209This is what every Fat Shack customer looks like
>>2881210This is what most Carl Jr's customers look like
>>2881209>be sold that>buy thisSAD!
>>2881210>>2881211Thus demonstrating there is a difference between /ham/ and a ham beast.Also: https://youtu.be/6XHwygN9CKM
>>2880874Got my board today in the mail. Damn network spans around 24km. At least thats the furthest point that sens its gps info. Very nice in my opinion.
>>2881262That video isn't even correct, stop posting that soishit
>>2881313Losing your sleep over the failure with "Q"?
>>2881318not my cred that's going down the shitter.it shouldn't be this thread's problem, either, buy an ad.
hit by the tism bug and decided I wanna get into ham stuff. watched a buncha videos and what not. I decided to start small since i'm still seeing if this hobby even is for me like in practice as opposed to just me enjoying learning about it, so I got a handheld instead of a base station cause of price. my logic is, if i enjoy the handheld and have fun with that and am able to use that to make connections local find other hams etc, then from there i can get more hands on help setting up a base station learning stuff i can't just learn from reading or watching online. i've been studying to try and prepare for a exam. i haven't set any date or got anything figured out but i'm shooting for end of January so i got a fair amount of studying to do. my main focus right now is on Technician because (and please please pretty please correct me if i'm wrong) that's all I'd need to be able to broadcast on the UHF/VHF handheld i'm using. I still want to try and take my general and pass that the same day though, just so that when i wanna get a base station and drop that money down i won't have to worry about passing another test or going through that again. the radio i asked for is the TYT TH-UV88 Dual Band Analog Two Way Radio pictured. I'm excited to try and learn more about this world. I'm not someone who's super great with technical knowledge, i wanna be able to learn how these machines work and retain it. as well, I love these forms of communication and i find the concept of being able to talk to people through this radio fascinating and it has a lot more appeal to me then social media or discord calling or whatever. plus it's just margepotato. I'm trying not to make this a "give me all the info you can" post cause the OP have some good stuff and I don't wanna risk being annoying or derailing a thread by asking a buncha newbie questions that have been asked a million times b4 LOL.
>>2881390attached image but it didn't upload the image that's actually great and wonderful and great
>>2881390>hit by the tism bugIn that case, ultra high speed telegraphy is probably your thing. Legends such as Theodore Roosevelt McElroy simply must have been on the spectrum.
>>2880831Nvm i am just retarded and it just looks like 70cm is quiet where i live. On an unrelated note did i set my sdr to be too sensitive or is LoRa really shitting bricks across the spectrum?
>>2881543Equidistant identical traces are sure fire indicators of front end overload.The continuous horizontal lines must be some form of wide band noise, perhaps arcing.
>>2881580Are you sure that the horizontal lines are off band noise? It also happens with whatever is on the right side, maybe wireless m-bus i'm not sure. I was looking at the spectrum to see how LoRa looks but the devices close to me make these wide bands when they broadcast. The legal limit here is 27dbi, is that a lot? In any case i plan on driving to other locations with LoRa traffic to see if other devices are also so noisy.Also is this just my SDR settings being too sensitive? I am boosting the gain by 20-40 db and i focus the waterfall at low end signals. When i leave it at mostly default the wide band noise is very tiny but weaker signals like the one on the left are nearly invisible.
If I hook a efhw to a pole at a 45% on top of a mountain. Dose the orientation mater. Like is it directional.
>>2881390>so I got a handheld instead of a base station cause of priceSmart. Off to a good start.>then from there i can get more hands on help setting up a base stationIf you judt want to focus on local comms, this will help. However, your antenna is very important.>that's all I'd need to be able to broadcast on the UHF/VHF handheld i'm using.Correct. >still want to try and take my general and pass that the same day though, You can try, have at it. Some end some end up doing it, but imo it's just better to focus on one at a time.>TYT TH-UV88It's an "okay" radio. I have lots of unlocked just to handout for situations instead of the normal go-to: Baofeng UV-5Rs. The main things I like about it is that it is cheap and you can get batteries that are usb rechargable. So, I can also hand out usb battery banks so if they need recharged, it's there.>excited to try and learn Don't get manic about it. It's the hobby of a thousand hobbies. It's easy to go too far.>I'm not someone who's super great with technical knowledgeI'm not either and I have the Extra license.
>>2881593>Are you sure that the horizontal lines are off band noise?Not sure about "off band" but the noise is wide band and some is in the band you see but a lot os also outside the receiver bandwidth, perhaps also outside front end bandwidth.>It also happens with whatever is on the right side,Not sure what this means.>maybe wireless m-bus i'm not sure. I was looking at the spectrum to see how LoRa looks but the devices close to me make these wide bands when they broadcast. The legal limit here is 27dbi, is that a lot?dBi is used for antenna gain and 27 dBi should be fine. It says nothing about power.>In any case i plan on driving to other locations with LoRa traffic to see if other devices are also so noisy.That is a good idea. Just make sure it is a low noise environment.>Also is this just my SDR settings being too sensitive?My guess it is not so much the sensitivity as ouyt of band noise that overwhelms the front end, leading to clipping in the ADC and thereby distortions.>I am boosting the gain by 20-40 db and i focus the waterfall at low end signals.Is that analogue amplification of just zooming in on the display?>When i leave it at mostly default the wide band noise is very tiny but weaker signals like the one on the left are nearly invisible.Good filters will help a lot, either band pass filters or broadcasting band rejection filters.
>>2881684so it will be sloped ? if yes, then it will be almost omnidirectional
>>2881726>>Are you sure that the horizontal lines are off band noise?>perhaps also outside front end bandwidth.That's what i am concerned about. Is it the SDR getting overwhelmed and sort of freaking out when strong signals are received or are they actually this noisy?>>It also happens with whatever is on the right side,>Not sure what this means.I mean that it is not only LoRa being this noisy but also whats between 868.9-869mhz, the right side of the screen. These are probably smart meters sending data and they are on the weaker side which is why its weird that my SDR shows them so distored. I know that this is an ISM band but even then some quality of the transmitter is required. Quality that would not shit noise across the spectrum.>>maybe wireless m-bus i'm not sure. I was looking at the spectrum to see how LoRa looks but the devices close to me make these wide bands when they broadcast. The legal limit here is 27dbi, is that a lot?>dBi is used for antenna gain and 27 dBi should be fine. It says nothing about power.My mistake. I think what i mean is 27dBm/500mW. The power that the Lora/Meshtastic devices use by default. You can tell if its a Meshtastic node by looking if its in the P sub-band, there they have kilometers of range. Weather stations and other sensors don't usually use that much power. The noise on the lower part of the screen was caused by such a device. But again i don't know if its "actual" noise of if its the SDR freaking out. >>In any case i plan on driving to other locations with LoRa traffic to see if other devices are also so noisy.>Just make sure it is a low noise environment.That's something i have no control over. My plan is to follow a Meshtastic map and just look at how the nodes there behave.>>Also is this just my SDR settings being too sensitive?1/2
>>2881726>>Also is this just my SDR settings being too sensitive?>My guess it is not so much the sensitivity as ouyt of band noise that overwhelms the front end, leading to clipping in the ADC and thereby distortionsIm not a professional in this field but i dont believe that devices with that sort of issues would be on the market here. Some interference on the ISM bands is ok but surely that sort of jamming would not be allowed.>>I am boosting the gain by 20-40 db and i focus the waterfall at low end signals.>Is that analogue amplification of just zooming in on the display?Its just on the computer. If i leave the software gain on 0dB i dont see anything with my antenna. Obviously this increases noise but if its just after the signal has been processed how come 'strong' transmissions drown out the weaker signals? >>When i leave it at mostly default the wide band noise is very tiny but weaker signals like the one on the left are nearly invisible.>Good filters will help a lot, either band pass filters or broadcasting band rejection filters.I dont have any hardware besides my SDR, laptop and antenna. I am however looking into some filters as these 'harmonic lines' are very annoying.2/2
>>2881734adding that the strong signals have some echo effect. The same happens with some FM stations. The signal shows up multiple times at the same time. Its also legible but weaker than the main source.
>>2881732>That's what i am concerned about. Is it the SDR getting overwhelmed and sort of freaking out when strong signals are received or are they actually this noisy?I don't have an RTL-SDR myself but I am planning to get one, nevertheless I haven't seen that much noise on vairious puctures and YT clips.Remember a SDR has an analogue frontend and a digital back end, with the ADC separating both. While your digital view might not show anything specific wrong, the front end might still be overloaded. To check for that, use an attenuator and check the full spectrum for massive spikes. those will have to be filtered out.>I mean that it is not only LoRa being this noisy but also whats between 868.9-869mhz, the right side of the screen. These are probably smart meters sending data and they are on the weaker side which is why its weird that my SDR shows them so distored. I know that this is an ISM band but even then some quality of the transmitter is required. Quality that would not shit noise across the spectrum.You will have to view the entire spectrum to check, band for band. >My mistake. I think what i mean is 27dBm/500mW. The power that the Lora/Meshtastic devices use by default. You can tell if its a Meshtastic node by looking if its in the P sub-band, there they have kilometers of range. Weather stations and other sensors don't usually use that much power. The noise on the lower part of the screen was caused by such a device. But again i don't know if its "actual" noise of if its the SDR freaking out.A 500 mW node is unlikely to cause problems and in any case it would be intermittent. Some of your issues seem constant. The conclusion is that you will have to scan the entire spectrum, and I would expect some kind of broadcasting issues.
>>2881734>Im not a professional in this field but i dont believe that devices with that sort of issues would be on the market here. Some interference on the ISM bands is ok but surely that sort of jamming would not be allowed.You would be surprised. Inverters for solar panels and LED lighting are notorious for massive broadband noise, and it is supposedly purely coincidental that these are made in China and that CE here means China Export. We had an airport jammed out of the airbands and only then did the authorities get up and look for the source. It turned out to be a gigantic LED installation. When ordinary people complain about radio noise they never reply.>>Is that analogue amplification of just zooming in on the display?>Its just on the computer. If i leave the software gain on 0dB i dont see anything with my antenna. Obviously this increases noise but if its just after the signal has been processed how come 'strong' transmissions drown out the weaker signals?Computer gain is just maginification on the digital side and will not reveal front end issues.>>Good filters will help a lot, either band pass filters or broadcasting band rejection filters.>I dont have any hardware besides my SDR, laptop and antenna. I am however looking into some filters as these 'harmonic lines' are very annoying.The good news is that making your own filters is not hard.
>>2882015>You will have to view the entire spectrum to check, band for band. Well there are often lines and sometimes huge hills on the spectrum. Now that i think about it the frond end is probably overloading. Al-tough it seems like even LoRa signals from kilometers away can quiet down the entire spectrum while they are broadcast. Maybe living next to a cellphone tower is bad for radios.>You would be surprised.Not so much anymore. Turns out that a majority of issues come from my computer and monitor being turned on.>The good news is that making your own filters is not hard.I know that i could block regular radio and cellphone stations but is there something against broadband noise? Wouldn't it quiet down everything? Anyways i traveled to a LoRa node yesterday but could not get good readings ar ground level. There are others nearby however and those will be my target tomorrow. If everything goes well i will have looked at three of those tomorrow.
>>2882095>I know that i could block regular radio and cellphone stations but is there something against broadband noise?You cannot block noise as such, only frequencies/bands and then everything on that frequency/band. You can get commercial filters here:https://www.rtl-sdr.com/buy-rtl-sdr-dvb-t-dongles/The simplest is to use a tuned filter that only lets through what ytou want and nothing more.>Wouldn't it quiet down everything?No, only what is in the bands you reject. You can get high pass, low pass, band pass filters and notch and band stop filters.
>>2864456FTFY
>>2882128>seething
>>2882128>couldn't triangulate the baofeng user award
Made my own shitty youloop antenna because I’m a poorfag.Gonna make a shitty receiver with some transistors next.Hopefully it will all work.
>>2882748the true spirit of amateur radio/diy/
>>2882748I thought coax is shielded and all of this stuff. How is it supposed to work as an antenna?
>>2882877The original one comes in cute boxes but other than that it doesn’t really have any shielding. I literally just copied the designhttps://www.hamradio.me/antennas/airspy-youloop-lf-mf-hf-mobius-receive-antenna.html
>>2882902I mean the cables. They are coax right? And coax is known as this shielded low loss thing. So how can you use it as an antenna? Interesting stuff.
I don't get it, is 40 meters just rampant shitposting? What's the point?https://voca.ro/1lmh0RiXhgkz
>>2882937lol were you on 7.200?but all bands are just boomers ragchewing
>>28829457.26
>>2882933Far more to coax than just shielding. Read up on theory as it's a fascinating subject to get acquainted with and will explain things that many hobbyists find baffling.
>>2882937Rather than climbing up in tall masts like this, why aren't hams instead erecting their own private Wullenweber?
>>2864357I got my first ever radio, a handheld Yaesu, and read the manual to figure out how to tune into FM music radio. I'm going to go to my county's amateur radio club next time they meet... They look like a bunch of balding guys who would be dying to teach a newcomer. In the meantime, I'm going to try to hear some of the local frequencies from the radioreference link in the OP. Don't worry, I won't transmit.When was the first time you guys ever got into ham and why?
>>2883224for me it was while I was in college the local club did the class for tech there. So I got tech but never really transmitted. Then a year or so ago I decided I wanted the general. Tested for it and bought some gear. In my area VHF/uhf is pretty dead so HF was the only thing of interest. Haven't got around to building a tower or anything though. Just a efhw antenna strung up
>>2883069Do you have any idea the land size and expense behind it? The closest your regular ham can come to something like that are phased verticals. Even then, the phasing is a bitch to deal with when you want to change frequencies, even if swr measured bandwidth is okay. Complicating the setup with a 4 square are larger setup is definitely done and possible, but I've never seen anyone go beyond a 4sq, because the phasing network would be ridiculous. Keep in mind, the type of gain, both measured and by function, depreciates, while the cost skyrockets. The difference between a 4sq and a 8 phased setup won't be as major as you'd think, but would require more than double the cost between phasing networks, coax, radials, etc.This is all pointless for bands below 40m by the way. Because you can just throw up a significantly cheaper beam on a 40ft tower and be done with it. A hexbeam at 40ft would out-perform a 4sq vertical on 20m, while also being resonant on all the hf bands below it (a 4sq is monoband only). Likewise, even a super expensive 40-10m yagi would be cheaper to erect at 40-60ft than going into 8 phased verticals for 40m, and also perform much better on top of it, despite not having instant direction changing.Verticals have their place. If I wanted an 80m antenna, I'd erect a single 80m vertical and get on the air. They make great antennas, and a proper 80m beam is too difficult to raise for someone like me. A single 1/4 wave vertical needs no matching network, no fluff or bullshit. Coax connected to steel pipe, coax shielding connected to ground radials, push tx.
>>2883316Yes, I know it can be big, the side depends on the wavelength and the number of elements. To avoid ambiguities they say the elements should be spaced less than one half wavelength apart. Strictly speaking, that is not true, as long as you have a few close spaced elements to resolve an initial ambiguity. A wide aperture is good for angular resolution and possibly also elevation.Phasing can be done in analogue form, which is how it was done originally with the spinning goniometers directly coupled to the antenna via long coax cables. In 2024 you can do it digitally, and you can have receivers in each element and ethernet cables to a fully digital goniomenter. Wullenwebers used 2 or 3 concentric rings, one for each band, but there are tricks to make do with a single ring where each antennas can use traps and several receivers, one for each band.
>>2869608>I wish I had the real estate to do something like that.I have a small lot with a shed that I'm starting to run antennas to. Inside the shed is an old PC which is running OpenWebRX+ and is connected to my network with ethernet.So far I only have 3 RDL-SDRs running, but hope to double that (while also upgrading SDR dongles).From my shack I can do to OpenWebRX+'s IP address and see something like pic related.It decodes FT-8, pagers and about a dozen other things if memory serves right.It's sweet for monitoring the repeaters or seeing if 6 meters is opening or if X HF band.My backyard is only 30 ft X 60 ft
>>2883224>WhenI first heard of ham radio in 1982 when my electricity teacher in jr high mentioned he used to be one. His classroom had various shortwave radios along one wall. He was a former telco guy. The concept of being able to transmit instead of just listening I found naturally intriguing as at that time I had a cheap multiband radio from Simpson-Sears that had some SW coverage that I casually listened to.But it was the summer of 1984 while earning some money cutting lawns in my neighbourhood that the radio bug bit. Had this guy with wires running all over the place on his acre and I found it a PITA driving the mower around them all. I asked him if he was trying to pick up a TV station or something as around this time I was experimenting with wire antennas trying hard to increase the signal strength of the only FM rock station in my region so I could hear it in stereo. He said he was an amateur radio op and I was instantly interested. Lol, I asked if that was like CB radio. No! :^)He said he'd show me his station next time. Following saturday he calls me up on the pretense of cleaning up his yard of some branches. I was there ~45 minutes and he hails me over, hands me an ice cold Coke, and says enough of that and invites me inside to see his wife and station. It's still vivid in my memory: I saw a wall full of equipment! It was actually two stations side by side as his wife was licenced as well. But when he called and that W6 answered back.. THAT was the moment when I knew I found my hobby. Hard to explain the feeling. I didn't get formally licenced until 1992.
>>2883069>why aren't hams instead erecting their own private Wullenweber?Imagine the massive copper grounding system. I drool with envy and it would be a copper thieves wet dream. heh.Because a Wullenweber is only good for instantaneous HF direction finding. I don't think they've ever been used for transmitting. Anyone know the gain figure for them? I've been looking through the navy-radio site looking for numbers.
>>2883534>Because a Wullenweber is only good for instantaneous HF direction finding.That too but also more. Directivity also excludes QRM.> I don't think they've ever been used for transmitting.They have, such as the pair at Impreial Beach. Admittedly this is not very common, at least not according to public sources.> Anyone know the gain figure for them?Not sure but you could add the signal for all the elements used, which is not fully 180 degrees of a circle.>I've been looking through the navy-radio site looking for numbers.Not sure they would ever admit much.. Even angular resolution is not well disclosed.
>>2883534>Anyone know the gain figure for them?Some declassified stuff here:https://apps.dtic.mil/sti/trecms/pdf/AD1207196.pdfThe 3000+ ft size seems particularly appealing to me.
>>2883930For that much wire why not do what Art Bell did and make a mega loop?
>>2883534>Imagine the massive copper grounding system. I drool with envy and it would be a copper thieves wet dream. heh.Buld it atop a wide water tower and you get elevation and grounding for free.>>2883935An array provides a lot more flexibility compared to a single loop.
>>2883950You're talking about tens of thousands for a vertical array even at very modest sizes, unless you go back into 4sq sizes. It just seems pointless. I could put up a massive yagi array that'd embarrass even the most complicated non-government funded vertical array setups, for a fraction of the cost and better performance.
>>2883950>>2883991What about this?https://www.antennas.com/product/lpv-1608/https://www.antennas.com/product/ean113-3/
>>2883994Smaller verticals
>>2883991>You're talking about tens of thousands for a vertical array even at very modest sizes,That is the cost of a high end rig such as FTDX-9000D, so rich Americans would see no problems here, especially if it would let them dominate the bands.>unless you go back into 4sq sizes. It just seems pointless.Antenna tech is a big part of the hobby, always has been.>I could put up a massive yagi array that'd embarrass even the most complicated non-government funded vertical array setups, for a fraction of the cost and better performance.Please du tell more. A CDAA will be able to monitor 360 degrees continuously without mechanical rotation of any part. A yagi will have to be turned to scan.
big brain ideabuy old am radio tower use as giant vertical antenna
>>2884009>Ftdx9000d = ~9k>CDAA $800,000 to $900,000 1970s (7.5m today)Even downsized it'll be way more than a ftdx9000d. >you have to turn itOh no! I can't use it for radar, what a shame when trying to dx with a country when I have propagation maps up and can already tell my most likely dx abilities. 4sq arrays already offer instant switching by the way, and radiation patterns give it omnidirectional capabilities. Even then, a multi band yagi or cubical quad will out perform it, just turn it after spotting.There's a lot of diminishing returns in amateur radio, and the cost increases exponentially with every db gained. >>2884012I've transmitted on a 240ft am tower on 80 and 160m. Amazing transmit, less than amazing reception. It was in the city though, and the noise floor was awful.
>>2884014so am tower with a beverage would be the play?
>>2884015An am tower in the middle of nowhere would be sufficient.
>>2884012Isn't that what AM stations actually do? I thought they used the tower itself as the radiating element?
>>2884186yesbut they just use it for transmittingwe're saying for receiving and transmitting
>>2884198I've been long toying with the idea of building twin 40m and 80m 1/4 wave verticals on opposite ends of my property. I've done so for 20m and it works well. This of course could never compare to a 200+ foot am radio tower.
>>2884447Load up your fence for lulz.
>>2883578>I don't think they've ever been used for transmitting.>They have, such as the pair at Imperial Beach.Now that I didn't know. Is there a source on this? I'd like to read up more on it.
>>2883578>Even angular resolution is not well disclosed.Is that the beamwidth?I've found some gain figures: A FRD-10 using a 120 monopole system has a theoretical gain of 21db but the best they could tweak it was 19 db. I believe this was from someone who worked at the Imperial Beach site. While giving no figures he said the F/B ratio was excellent.I forgot I had a book that has a decent sized section where it talks about CDAA's. "Red November" by W. Reed. Enough detail that a knowledgable person can understand clearly but lacking in the itty-bitty technical details I so desire. :^) Anyways, in it he mentions that up to about 1962, American CDAA's were about as accurate as WW2 HFDF sites.. maybe slightly worse. The Soviet 'Krug' ones were more accurate. I stumble on the remains of former Krugs when browsing russian territory with Google Earth. Somewhere I have a list and a KML file for them.
>>2884447>we have an actual boomer ITTI thought boomers didn't post here on 4chinz--only Gen X and Zoomies.
>>2864357People like that reply guy need to be beaten to death.
>>2884533Remember, you can never leave. Also, >>2883533 was in jr high in 1982 and is unlikely to be a spring chicken. For my part, I was a Morse code operator in the military.
>>2884457>>2884533Not my pic, just an 80m vertical.
>>2884512>Is that the beamwidth?Strictly speaking, no. There are tricks such as superresolution that gets you below full width half intensity measure.>I've found some gain figures: A FRD-10 using a 120 monopole system has a theoretical gain of 21db but the best they could tweak it was 19 db. I believe this was from someone who worked at the Imperial Beach site.Was that cable loss?>While giving no figures he said the F/B ratio was excellent.I can believe that, this was the purpose of the screen behind the antennas. Wullenwebers always have a screen but there are phase analysing arrays that do not use a screen and then can employ far more antennas per target.>I forgot I had a book that has a decent sized section where it talks about CDAA's. "Red November" by W. Reed. Enough detail that a knowledgable person can understand clearly but lacking in the itty-bitty technical details I so desire. :^)We are definitely on the same wavelength here.>Anyways, in it he mentions that up to about 1962, American CDAA's were about as accurate as WW2 HFDF sites.. maybe slightly worse.That is hard to believe.>The Soviet 'Krug' ones were more accurate.That is even less credible. The Soviets took the scientists the Americans didn't want in Operation Paperclip. Why would tier three do better? I must admit that the Krug has some positively baroque details I cannot understand the utility of, and it is know that they covered up to 50 MHz, but more accurate?? That is hard to believe, especially as they had a single ring and were very close to the original German design.>I stumble on the remains of former Krugs when browsing russian territory with Google Earth. Somewhere I have a list and a KML file for them.There are discussion fora where people aggregate such data. Other fora are full of misinformation and garbage, so be sceptical.
>>2884587>they had a single ringTurns out a German intelligance agency had a huge CDAA built not far from the site of the orignal prototype. Some images are rather blurred but it seems they have 4 rings.
80m boomer banter gives me fucking life.https://voca.ro/1gHg8bDBFCKd
>>2884447I wanna make a 40m and move my 20m to the back yard. 1/4 waves just work.
So how can one anon make a modern CDAA? Perhaps a receiver in each antenna element and a ethernet cable to the goniometer will avoid problems with losses?16 elements apace half a wavelength apart for the 40 m band means a radius of 51 m. Clearly I need a larger garden. Aiming for 10 m wavelenth it is more compact, might work on 40 m band with outrigger antennas, but I am not sure about the maths for this. Some literature suggests the use of "manifolds" but I am unfamiliar with this tech.
>>2884920What's the point when you can make a directional beam and identify a signal's direction that way? What does instant signal direction identification provide in a scenario where you have only 1 reporting station in 1 location and can't triangulate anyway.
>>2884587Cable loss? I will try to find out. He said it was 75 ohm nominal impedance. As we both know the lengths had to be meticulously accurate.As for the authors' Krug accuracy claims, I was quoting what he said in his book where he details the challenges the NSG had getting the hit accuracy improved during the beginning of the Cuban Missile Crisis. My understanding is that up to that point Boresite, while an important project, didn't get top priority until the crisis started and the presidential request that it be improved so they could track the four Soviet 'Foxtrots' lurking nearby. The authors father was intimately involved in that and was also the one who discovered the Soviet sub burst signals. I also didn't know the first two Krugs were built to track Sputnik and other space shots.I have the book but I also have a 4 MB pdf version I can upload for you if interested.By the 1970's the Krug system must have improved their accuracy. It is said that while tracking a Soviet Tu-95 bomber flying over Canadian territory while en route to an air show, the Russian air crew regularly report their position back home via CW. During this flight, the Krug network was using the aircraft transmissions for check bearings and was reporting the bearings in tenths of a degree. Backplotting of these bearings is said to have confirmed their accuracy.The list of Sov Krugs I have I think came from a declassified NSA file. It included coordinates. >be skepticalReagan said it best: doveryai, no proveryaiBtw, Happy New Year all.
>>2884943>I also didn't know the first two Krugs were built to track Sputnik and other space shots.I stand corrected. It wasn't the first two built. One must refrain from posting while consuming rye & Cokes. :-)
>>2884927There isn't a point, really. I think people just see big antenna and say "I want." There's certainly an abundance of phased arrays in the amateur world, but it's for fulfilling amateur practices.
Is it possible to "fan" a horizontal loop, or is there no need since it's "resonant" on harmonics? I mean, cobwebbs are fanned, why not big loops?
>>2884927The point is to have a selective directivity. With a 1 degree lobe on a monster yagi you can only hear in one direction, with an array you can hear one and also at the same time hear the guy is also communicate with someone along a different direction. And first and foremost it sounds like a fun project where I can apply modern DSP tech to get better results. There is so much QRM these days you need a way to cut down on the noise.>>2885045>There isn't a point, really. I think people just see big antenna and say "I want."Sure, and a Krug has a lot of weird stuff I want to read more about, pic. related.>There's certainly an abundance of phased arrays in the amateur world,Is there??>but it's for fulfilling amateur practices.
>>2886220>Is there??Absolutely, I spoke to one guy who had 4 hexbeams phased together.
>>2886220>There is so much QRM these days you need a way to cut down on the noiseA beam does this. I don't understand why you can't just apply the theory to a 4sq.
Kinda off-topic, but I think I'd have more luck here than /g/.I want to get into meshtastic, but I kinda want to put up a permanent hub node high up somewhere, with a solar panel and deep-cycle battery to keep it running even in event of a big power outage. Do I just buy two of the same NRF-based meshtastic nodes, use one personally and another as a hub? Would using a Meshtastic node with GPS be preferred for this?I see that Meshtastic isn't compatible with LoRa gateways, which is unfortunate since there's already wide gateway coverage locally, and such a mixed comms network would allow communication both locally, and further abroad when the gateway has internet connection.For the power side, I'd probably just add a CC/CV buck converter from a ~10W PV panel going to a big (50-100Ah) 3.2V LiFePO4 prismatic cell, with a regulator from that to the node. Should last decades.Any thoughts?
>>2886660*yawn*
Just got my ticket and looking to pick up a good do-it-all HT for UHF/VHF. I'd like to get something that can experiment with digital modes, and packet messaging like RTTY or APRS.Currently thinking about a Yaesu FT5DR, but also wondering if I should just spend the extra $$$ for a Kenwood for the KISS TNC and (more importantly) the physical keypad. Opinions?
>>2886792Get on HF and leave the hts for scanners and analog toys. You got the ticket, time for big boy pants while 10 is alive and well. Can still do rtty, packet, ft8, sstv, etc
>>2886796I'd love to into HF but I'm in the middle of a big move at the moment and living in a temporary apartment while my previous place sells. So I can't really set up a big antenna and base station right now - I'm limited to mobile or HTs. My goal in the future, when I can afford it, is to set up a Shack-in-a-box style HF mobile station that I can transfer between my car and a hardcase, for things like POTA. But at the moment with my ongoing move, I can't set all that up cheaply enough so I'm settling for an HT. Should I just settle on a cheapo boofeng for now, or maybe a moderate option like an FT-70?
>>2884943>As we both know the lengths had to be meticulously accurate.Yes, though they did frequent line length compensation. Not sure why that was necessary but it seems they had to.>I have the book but I also have a 4 MB pdf version I can upload for you if interested.Yes please.>By the 1970's the Krug system must have improved their accuracy. It is said that while tracking a Soviet Tu-95 bomber flying over Canadian territory while en route to an air show, the Russian air crew regularly report their position back home via CW. During this flight, the Krug network was using the aircraft transmissions for check bearings and was reporting the bearings in tenths of a degree. Backplotting of these bearings is said to have confirmed their accuracy.In an eeriely similar story, the US tracked a Soviet plane that read outs its position and used that for calibration. The story seems a bit strange since the US could have used own aircrafts for calibration outside the Soviet Union, and radar tracked aircrafts inside the Soviet Union, since a lot of aircrafts, also civilian ones used HF>The list of Sov Krugs I have I think came from a declassified NSA file. It included coordinates.I have seen a similar set of coordinates on the net, people have spent a lot of time viewing Google Earth. Sole lists here:https://alcpress.org/military/wullenweber/>Btw, Happy New Year all.Thanks, you too
>>2886798>big antennaYou can't setup up a dipole for 10m?
>>288679610m is poppin?
>>2886806We're at the peak of the best solar cycle in >30 years...
>>2886807sorry hadn't been paying attention been remodeling the ham shack
>>2886805Probably not. The temporary apartment I mentioned is my inlaw's and they freak out at the smallest things - for example they use their oven for "storage" and they had an absolute meltdown when we asked if we could put the oven rack back in and use it to bake something for dinner one night. We're living here to save money while the house is listed and sold, and lucky to be able to do that, so just kind of dealing with their dumb shit for now. Since it's their home and we're already imposing on their daily life, I don't really have the right to say anything... and if the oven incident was enough to freak them out I don't even want to think about what would happen if I tried to stick an antenna on the roof. I won't be in a position to set up anything like that until we have our own place, likely at least a few months away.At the same time I'm dying of boredom here with no interesting projects to work on, hence my renewed interest in radio and getting an HT to essentially hold me over till then.
>>2886220>With a 1 degree lobe on a monster yagi you can only hear in one directionUsing wire beams, you can easily make a reversible yagi using only a relay switch and coil to make the parasitic element a reflector or director. Obviously this doesn't compare to a static built beam, but it works well. From the US, make 1 set NE/SW and the other set NW/SE and run both sets to a switch by your radio. Then use the remote relay to engage or disengage the coil in the parasitic elements to change directivity. All of this is near-instant for back/forth switching, and everything involved outside of masts to tie up the wire comes down to <$100.Throw a tuner in-line and you can do this with vertically polarized square or delta loop antennas, assuming the loop is big enough to support the lowest band desired. Current hardware and software support antenna signal bias if you want. If you can get your relay switch to communicate with that software, it'll automatically switch to the strongest signal between setups, and block everything else out. Manual switching can be done to listen to weak stations and attempt to block out loud qrm.
A Wullenweber dominates the landscape: https://www.youtube.com/watch?v=uh88Y2_33GI
>>2887109Yeah that's why nobody uses them.
>>2887155So, a new found US form of modesty and humility? How unexpected. I thought Brian Shul was the only one to pull that off.>>2886220 >>2886803I read somewhere that krug covered the HF band and up to 50 MHz, yet all the pictures show a single ring. FRD-10 has two rings of antenna elements and FLR-9 has 3 rings, so how did they pull this off? And only the German version needed "hats".
>>2886807solar cycles arent real
What are the differences between aprs, wspr, and lora? Am I missing any others?
>>2886803>>I have the book but I also have a 4 MB pdf version I can upload for you if interested.>Yes please.Sorry for the delay. Here you go. It's on a 3-day retention, let me know if you need a re-up: https://litter.catbox.moe/vajwaa.pdf>>2886806Last weekend I heard a 10m FM repeater for the first time since Cycle-22.
>>2887522>Here you go. It's on a 3-day retention, let me know if you need a re-up: https://litter.catbox.moe/vajwaa.pdfGot it, thanks!
I'm trying to see if there is anything wrong with my design, as of now, when I try making some changes on the adjustable capacitor, I keep hearing nothing but noise and the frequency doesn't seem to change.That aside, the amplified noise seems to have a peak to peak amplitude of 4V.I'm using a wire antenna of around 7 meters in length.The FFT on my oscilloscope seems to show a large mound around the 400kHz frequency, with some spikes there and there which correspond to the stations on my area.
>>2887737Could be your grounding, likely a compromise on your antenna causing noise in your circuit. Hard to tell without more details about your antenna and the grounding of your circuit / antenna design. Sounds like you already know your front end is being over driven. But also this schematic makes nearly no sense to me.I'm a useless electrical engineer, 30 solar rotations. Show me your bread board nibba.Holy shit the captcha is an actual retard filter, fucking impossible.
>>2887785>But also this schematic makes nearly no sense to me.the stuff on the left is just me trying to somehow simulate an antenna, and to see if the frequency response is what I want, it can be mostly ignored.The idea is to have the LC-tank resonator to select the specific band I want to listen to, and to amplify this signal, everything else is just impedance matching and amplification. I left out C5, since it made the gain way too high and it clipped a lot.> Show me your bread board nibba.I've got some bad news lolThe antenna I'm using is the Sangean ANT-60, which is the longest antenna I could find to be easily accessible in my country, without it being too cumbersome (the wife isn't going to like a giant loop antenna, which I'm not sure it can even fit inside the apartment).The antenna connector on the left is not grounded, since for some reason that made it receive some nearby FM station (not even sure how it demodulated the signal).The stuff on the right is just a buffer, a high pass filter, and a current limiting resistor to avoid torturing my headphones.
>>2887800>>2887785FUCK, I just noticed that the connector's sleeve and tip are shorted
>>2887800I don't know what value that trim cap is but it looks way too small.
ham is dead
>>2887348your mom isn't real.
>>2884512>"Red November" by W. Reed.The critics are enraged:https://www.amazon.com/review/R33RVKQB7NRWGS
>>2887822Supposedly, it is 120pF, I'll try replacing it with a DIY aluminum can resistor and see if it gives me a better range.
>>2887861Nah, your antennas must be dogshit, 40m was on fire with no room in the band last night. Not even contesting.
>>2887928>oh look this very small part of the ham frequencies has occasional slightly above normal traffic. ham is not dead it's on fire.KYS
Should i calibrate the vna with the antenna cable connected except the antenna ofc, or just as short as possible? It's 430-440M, about 20ft cable. This vna stuff is new to me.
>>2883578>Even angular resolution is not well disclosed.Got some information here:https://www.jproc.ca/rrp/masset.html>Bearings were read out to the 1/10th of one degree - pretty damn good resolution!.That is 10 km error at a distance of 6000 km, yes, that is pretty good. Also worth noting this detail that I never heard before:>The FRD-10 antenna ring could be phase switched between approximately 45 degree and 15 degree (some modifiable to 30 degree) arrival paths.The resolution isn't too far off this note from 1947 (declassified in 1978):https://apps.dtic.mil/sti/trecms/pdf/AD1207196.pdf>To produce the 15-minute azimuthal accuracy claimed for the CDAAThat is arc minutes, which is 0.25 degrees.
>>2887961>active frequencies are dictated by the bands that are propagating>10m isn't propagation at 1am, ham is DEADkill yourself retard faggot.
>>2887994dude. seriously shut up while you still can. I was on shortwave before you're dad came in some whore. I saw a shortwave where there was SW radio stations every where. SSTV all over the place. hams on every band that was propagating. the russian woodpecker interference. radio fax, RTTY, and all sorts of other interesting things going on all the time.now... crickets. maybe some recordings of a dead preacher. very rare radio fax. sometimes traffic on 40 meters. early morning chinese or japanese radio stations, and faggots talking about signal strength, and blathering on and on and on about nothing. you have no idea what SW was really like.muh 6mmuh repeatersmuh prostatemuh contestsmuh dead airand no it's not because I have a bad antenna. I have listened in to online SDR radios all over the world. the only place SW still has any real activity is europe and it's slowly breathing its last.oh lets listen to russians and Ukrainians troll each other! woop D fuckin' DO!
>>2887822>>2887801>>2887800>>2887785>>2887737Managed to fix it by replacing the inductor with an SMD one with a lower ESR. I'm thinking the quality factor of the axial one was terrible compared to my new ferrite inductor. Terrible selectivity, but now I'm sure it works. Might try to design a superhet now.Tuned in to "Radio La Sabrosita" if anyone cares :) https://emisoras.com.mx/sabrosita/
>>2886807Damn... still haven't got my general license yet
>>2888386could be worse you could have a general but a shit antenna setup and no good space for your radio gear
>>2888398There are plenty of compact rigs. And a UHF antenna doesn't have to be big.
Trying to slap together babby technician's first 10m rig. With no space for an antenna I'm limited to mobile only. I got a super cheap HTX-10 from an auction the other day, and an end-fed half wave wire antenna. Looking for the best mounting options for SUVs. I'd ideally like something like an 8' hamstick lip mounted on the fender or hatch - but with it that close to the car I'm afraid of it interfering with the ground plane. So I'm now leaning towards a flagpole hitch mount, with a collapsible 20' pole I can attach when I get to a suitable location, and just using some extra coax for counterpoise. Does that sound right?
>>2888431gonna do some pota?
>>2888452That's the idea yeah
